Bluetooth® wireless technology provides peer-to-peer communication between Bluetooth devices within a local area. Conventional Bluetooth® devices are adapted for use with a computing device, such as a mobile phone, portable computing devices, or a music player. Bluetooth® is a short-range radio link intended to replace cables connecting portable or fixed electronic devices. The Bluetooth® system provides a point-to-point connection or a point-to-multipoint connection. One Bluetooth® unit acts as the master of a piconet, whereas the other units act as slaves. In the point-to-multipoint connection, the channel is shared among several Bluetooth® units.
Some Bluetooth® connections incorporate two types of connections for a physical radio frequency (RF) link: a Synchronous Connection Oriented (SCO) links and Asynchronous Connectionless (ACL) links. The SCO link is a point-to-point link of a call connection type created between a master and a specific slave, and is used mainly for transferring voice data. One single master can have three SCO links at a maximum to the same slave or different slaves. The ACL link connects between a master in one Piconet and all the active slaves in a packet switching manner. The master can switch the packet with a given slave in a slot unit using a slot which is not reserved for the SCO link. The ACL link is mainly used for data transfer.